on my latest engine, I made some standoff's on my lathe, drilled out 3/4 of the length to just above the size of 10-24 allthread, then tapped the end that wasn't drilled too big, replaced 4 of the case bolts with the allthread, installed the spacers with the threaded portion furthest from the engine and tightened, I left enough of the allthread sticking out the back to go through the firewall and used nyloc nuts and fender washers on the other side of the firewall.

this method works well, although I haven't technically ran an engine with it, it's plenty strong, and allows for the least amount of bending in the weak allthread so it should actually hold up...

although this isn't a homelite obviously, it should show what I was trying to explain