RE: Midwest Extra 300xs Build
Looks good your getting there .About your engine and bolts ,you will want to use 1/4 -20 bolts scocket head caps screws and blind nuts work well for this And yes you will need stand offs . What I would do is to look at the side view of the plans and measure the distance from the engine box to the front of the prop hub ,then measure the length of your engine to get what you need for the length of the stand offs & bolts. Standoffs are usually 5/8-3/4 dia alum with a 9/32 hole drilled in the center ,if you have access to a lathe there easy to make.hope this helps some. Keep up the good work .
Oh I may have a alterntitive fix for my engine to get rid of some weight if so i'll let you know.
One more thing for I forget you may want to add some scrap wood to the rear wing bolt plate on the sides next to the fuse to built it up to match the wing saddle .1/2 wide is enough just so it will clear the bolt holes.It wont be so apt to pull on the plate this way and tear it loose from the fuse if you over tighten it. I did both front and back on mine .