Fork seal driver 1982 GPZ750

Anyone know the inside diameter of the front fork for a 1982 GPZ750? I'm looking to buy a seal driver from MotionPro, but don't have the specs, Thanks. Mark

According to the diagrams at Partzilla, the 82 750-R1 has the same fork seals as my 81 650-CSR. The csr's upper fork tubes are 36mm. I use 1-1/2 pvc pipe & fittings to drive the seals. and place a good used seal between the new seal & driver as a protector. probably not necessary, but it's what I do.

Thanks for the info. After upgrading the rear shocks to Hagons, I decided it was time to rebuild the front end as well. New steering bearings, wheel bearings and gold valve cartridge emulators with single rate springs. After 95,000 loyal miles, its the least I can do for the old GPZ!