1970 Stepside Cab Mounts

[specks70]

Hello all, new to this forum and hoping it will provide information supporting my latest build. (1970 chevy c10 stepside)
This is my question. The rubber cab mounts were non existent when I purchased this truck. I completed all the frame and body work and am now wanting to install the newly purchased mounts. However when I installed there seems to be no room for the ones at the radiator core support. I've tried different configurations but nothing seems to work. I have searched this forum and have not found any results so I'm hoping that if I start another thread with this subject that someone can help. My truck is almost completed at this time so I hate to go and buy the assembly manual and LMC simply shows a picture. Hopefully someone can help with explaining a procedure.
I'll post a few pics of my truck build shortly.

Thanks in advance,
specks70