Replace rigid fork with short-travel suspension fork for under $200 (used OK, switching to threadless from threaded OK; standard 100mm QR axle preferred but 15mmx100 through axle OK; V-brake mounting bosses preferred but disk-brake-only OK)
Seems like short travel (e.g. 60mm) will be needed to fit A2C; has low-end fork suspension technology advanced enough that a recent cheap air shock would be better than a 15+ year old used fork like maybe a Judy?
1996 Trek 950 mountain bike; 26" wheels, cro-moly frame, original rigid chrome fork using 1 1/8" threaded headset.
Trek tech manual says geometry is designed for axle-to-crown race (A2C) distance of 408-430mm, but I would be OK with up to 440mm.
Tech manual link: http://www.vintage-trek.com/Trek-Fisher-Klein-Lemond/1996specmanualTrek.pdf Bikepedia link: https://www.bikepedia.com/QuickBike/BikeSpecs.aspx?item=50637