Georgia,
My husband was about 195 and 5' 11"and I about 130 and 5'6"when we were doing those kind of transfers...not as big a difference as you. We were able to do them until he lost the strength to support his own weight after I pulled him up with a transfer belt. Then we went to a lift. I am guessing you will have to go to a lift sooner than some people because of the size difference,. With the lift I can move him around all by myself even though he is completely paralyzed. But do push your OT or others to train you in good techniques--there are so many tricks--our OT was terrible and didnt help at all--I learned from a friend. Be very careful of your back!Also , the PALS tend to lose a lot of weight which helps with handling..my husband was eventually down to 145 and now is up to about 155.
Good Luck...and try not to worry about it too much until the time comes! (That's the trick with this darn disease, isnt it?!)
Beth