I don't know any tricks to install 98se FULL/OEM over OSR2.1, but the 98se upgrade edition will upgrade 95 any version. It is better to do a clean install. Different versions require different keys, a OEM key will not work on a retail, or upgrade version and what not.

I thought the upgrade version was for upgrading 98FE to 98SE, no?

Warlord is correct, there is a Retail full 98SE upgrade edition that will upgrade from 95 or 98 to 98SE. The 98SE Update edition only upgrades from 98 to 98SE. The retail full 98SE upgrade may not work on some OEM Win95 installs but should on all retail Win95 installs.
added: Even my retail Win98SE full version states that you can upgrade from Win95 or DOS and will install on a FAT16 partition as well as FAT32.

It appears my question is answered in the "Setuptip.txt" file on the install CD (which is not an "Upgrade" version):

" If you are upgrading from Windows 95 and want to preserve your current
settings, run Windows 98 Setup while running Windows 95, and install to
the same Windows directory on your hard drive."

Methinks I'll clone the HDD before doing this.

I guess I should add; this actually defeats something else I was hoping to do, installing 98SE over 95 while at the same time migrating it to another motherboard....

Was going to say Autoplay gives you this option. But I really wouldn't want to do it. Even if it was a fresh Win95 install with no software installed It'll keep a load of old redundant crap no longer needed.

If your swapping hardware, especially the motherboard, I'd do a fresh install. Give yourself a nice clean foundation to build off and clone this nice fresh pure Win98 install

chinny22 wrote:

If your swapping hardware, especially the motherboard, I'd do a fresh install. Give yourself a nice clean foundation to build off and clone this nice fresh pure Win98 install

That is, no doubt, good practice and good advice.

But I'm still looking for a way out of following it 😀

precaud wrote:

chinny22 wrote:

If your swapping hardware, especially the motherboard, I'd do a fresh install. Give yourself a nice clean foundation to build off and clone this nice fresh pure Win98 install

That is, no doubt, good practice and good advice.

But I'm still looking for a way out of following it 😀

fair enough, ignoring good advice is what makes us human 😉

I upgraded from windows 3.11 to windows XP and it was stupid slow.

DOS 6.11 > windows 3.11>95 upgrade edition>98se upgrade edition>ME upgrade edition>2000 upgrade edition>xp upgrade edition

take good advice always do clean install upgrading is stupid. 🤣 Just because you can upgrade don't do it.

how about 1 to 10
https://youtu.be/t0rCTZ_3TQ4

I've done many clean 98Se installs and understand the benefits. Since this is a low-priority project, perhaps even short-lived, I was looking for an expedient path.

I remember reading once that Americans eventually do the right thing, after having exhausted all other possible alternatives.

Perhaps this trait has finally gotten through to me 😀

Horun wrote:

Warlord is correct, there is a Retail full 98SE upgrade edition that will upgrade from 95 or 98 to 98SE. The 98SE Update edition only upgrades from 98 to 98SE. The retail full 98SE upgrade may not work on some OEM Win95 installs but should on all retail Win95 installs.
added: Even my retail Win98SE full version states that you can upgrade from Win95 or DOS and will install on a FAT16 partition as well as FAT32.

My Windows 98SE upgrade CD worked fine on Gateway's Windows 95 OEM version. However, said Upgrade version is a special education variant that I bought at university, and that included extra goodies on the CD (and AFAIK had no own product key).