Almost ready to change my brake setup but need some help

[old_1966_GMC]

its been a few months sence i havent got a chance to get on here like i used to everyday and research the thread well any ways i have a problem im ganna be swaping from drum to disk today only problem is i dont have a engine hoist so i was tryin to see wat can support my engine mean while i take the crossmember off and put the other new one i have from a 76 c10 will i have any problems if i just unbolt the bottom bolts from the engine mouts that are bolted to the crossmember will the engine mounts be able to support the engine still even though they are still bolted on the frame i hopein this make sence to u guys any help would be thankfull