I'm still wrestling with the cowl on my Goldberg Superchipmunk kit. I mounted the OS 91 surpass and when drilling holes for the mounts in the firewall - I noticed that the mount was going to be right up at the very top of the firewall (engine is mounted horizontally). So I lowered it a bit when drilling the holes for the blind nuts. Big mistake.

Now as I'm finishing the cowl, I realize the engine is about 1/4"+ too low. The cowl has to angle downward, requiring shims near the canopy to hold it facing downward. Also, as the cowl angles downward, it doesn't line up nicely behind the spinner. It creates a big slanted gap. Big bummer.

I'm thinking I want to re-mount the engine mounts and move the whole assembly up on the firewall. Should I remove the old blind nuts - or leave them and drill new wholes and try to wedge in new ones? Or I could just leave the whole thing as is and live with the tilted cowl.

Anybody ever have a similar problem?

I have a super chipmunk, and mounted the engine where it was supposed to go. I would say move the engine up to the require level, but remove and replace the blind nuts. I doubt you will be able to get new nuts in properly without removing the old ones first.

When mounted properly, the cowl does ride high giving the needed clearance.

Thanks Sprink,
It's going to be hard to remove the blind nuts - as I CA'd them in place.
I guess I'll try to punch them out from the front.
I'm still surprised at how high the mount will be to the top of the fuse.

To remove the blind nut, insert the bolt and tap gently with something soft (I use the plastic handle of a screwdriver). That should loosen it enough to get it out.

Harder to get them into their new holes.

From memory my engine mount rides about 1/8 inch over the top of the firewall.