Canopy Frame Reinforcement

I've got the canopy frame fitted (for now), drilled, and ready to rivet together. As I am looking at the canopy construction, when is the best time to drill, fit, and install the canopy frame reinforcements? Not sure if I have the terminology correct but these are the plates with the lightening holes that fit-up under the forward canopy skin. Maybe I'm not seeing it, but cant find a place in Van's instructions where it talks about the order to install them.

Also, I recall finding a website that manufactured Delrin type blocks that install on the lower roll bar frame. The blocks hold the back of the canopy frame into alignment on the fuselage once it is closed. Can anyone tell me where to find these?

Much Thanks As Always!

I fit all my canopy parts, forward, sides, back and installed to airframe. Then installed reinforcement to front to hold "square". It still has some give but much better after install. On the aft blocks go to www.bullerent.com. Buller Enterprises, Inc. I used his and the fit is great!

Good info! Thanks Terry!