clutch fork boot replacement

[macdaddy70]

I have a 70 GMC with 4 on floor. GOing to replace some rubber this weekend, one piece is the clutch fork boot. Is there anything I need to watch out for once I disassemble the linkage to slide new boot over fork? Seems I read where someone was doing this and the fork/throw out bearing fell out or became misaligned. Just making sure before starting.
also installing a foam seal that goes around the stick and under the hump. Truck did not have one. Any thing special instructions with installation of this piece. thanks