I use Compact Flash to IDE adapter, and have it in one of the open slots on the back.. I have a few cards (2GB for DOS/Win 3.1, 8GB for Win95, etc) and can just power off the PC and swap them when I need different storage sizes.

https://www.amazon.com/CompactFlash-40-Pin-Bootable-Adapter-Bracket/dp/B07V5DML2B/ref=sr_1_7?crid=PVII171CBMDR&keywords=compact+flash+to+ide&qid=1652655917&sprefix=compact+flash+to+ide%2Caps%2C82&sr=8-7

https://www.amazon.com/Transcend-133x-CompactFlash-Memory-TS2GCF133/dp/B000VY2BC0/ref=sr_1_14?crid=2XFZH5O2RM9QF&keywords=compact+flash+card+2GB&qid=1652655933&sprefix=compact+flash+card+2gb%2Caps%2C82&sr=8-14

The cards/adapter are pretty cheap and since CF is IDE based, they are essentially plug-n-play.