Work Sequencing

My fuselage kit is expected to arrive in March, which should be just about right since I expect to finish the wings in a few more weeks.
I've been reading about lead times for engines, especially the Thunderbolts, creeping up to 11 months or so, and recently I had a reason to call Stein and asked them about their panel lead times. If I remember correctly it was roughly around 6-9 months.
To avoid the frustrations that others are experiencing waiting on bits and pieces to arrive, I had thought it would be prudent to order the engine sometime soon (not knowing how long it will take to finish the fuselage kit, but my gut and experience tell me it will probably take me a year to finish it). After the engine arrives I understand there are firewall forward and finishing kits available, but I'm not sure what the right timing is to have the panel/avionics arrive. I'm going to have Stein build my panel, but should the avionics come before the engine, or the engine come first? Or does it matter?

The usual recommendation is to hold off on avionics for as long as possible, as they change faster than anything else. You don't want to have your first flight happen, and wish your avionics weren't obsolete (!). This is exaggeration of course, but don't buy them years early.
Vans often has, in the past, offered "specials" on engines/props, usually at the big shows like Sun N Fun and OSH. Order them then. The engine will come with long term storage oil. Plus engine prices seem to be going up a lot faster than inflation: think of it as an investment!!

I would also recommend taking advantage of Van's SnF specials including engine & prop combos. If your build is on a fast track, I would order avionics soon afterwards as installing harnesses and hardware is much easier early on in the fuselage build. It is very frustrating having to slow down your progress waiting for components.

A few data points. The last few years, the ?special ? has not been very special. If you order April-August then they throw in free shipping and thats it. Savings of about $300. Definitely not worth the delay. The $1000 off engine/prop combo is year round, no need to wait. I know in the past the specials have been better but these days with Lycoming backlogged I doubt they come out with anything better.

Also for avionics you might want to give Aerotronics a call. They had my panel delivered in 4 months, very happy with them.