Originally Posted by RICKSTUBBZ

Gregory,

I actually mount engines on that inverted angle intentionally. Keeps the exhaust on the bottom of the plane..Particularly when using stock mufflers.
I realize it is controversial with the majority. I have no problems. I have (and had) many 40 and 51 size engines mounted that way. As well as 90's That beast of an OS 91 should not care about that angle either... Just make sure the fuel tank is at the right height (middle of tank more or less at the middle of spray-bar)

To answer your question as to how to get the T-nuts in place.....
You can use 4-40 metal control rods, "ny-rod" even thick sting.
Fish your rod/string though the new hole and get it to fall out of the wing access area...or whatever hatch you may have..
Now put the new t-nut over the rod/string. Make sure it's in the correct direction.
If using metal rod now place nut and washer (ny rod ad a piece of 4-40 all thread then washer and nut
If using string tie a washer on the end
Carefully pull the t-nut into place and gently set it enough to stay in place. Let the rod/string fall back through the fuse access hole
Now insert the proper screw and washer from the front and gently set the t-nut permanently
If you desire place a little 30 minute epoxy on the t-nut before pulling it into place