On end would be no problem, tie it in place, damage will occour if it falls over. I kept a 90 roof up ended on it's side gutter for over a year. If you can hang it from the roof rafters so much the better. it's a big lump and takes up a lot of space. I'll be in the same situation if my rebuild ever progresses past the rolling chassis stage... I'm hoping to swap over the transmission and engine this week.
Diesels.....great when they're going and so easy to work on.