292 engine stands for K10

[landarts]

I am getting ready to start another new project build here soon on a 69 K10 that I picked up. The truck originally cam with a 292 motor according to SPID, build sheet and emblem on front fender. When I purchased the truck I also purchased a completely rebuilt 292 motor to go back into it and make it original again. I have done quite a bit of searching, reading threads and there seems to be a mix of answers out there. Just want to do this right one time.

So now what I have is the last P.O. removed the 292 motor at some point and installed a 327 or 350 in it. I have not removed the motor yet to verify exactly what it is. It looks like the motor perches are the typical ones that fit between the frame and are riveted on. Not like a standard C10 that has them bolted to top of frame and to the crossmember. I will be removing the motor soon to clean up firewall areas and prep for the 292 motor but need the perches and whatever else goes along to make it work. At this point I just do not know exactly what it is I am looking for.

If the items can not be sourced i dont mind fabricating whatever i need to make it work, just would love to do it the way it was back in the day if I can.
The picture below is one I found on a thread. Any direction on the subject would be appreciated.