Probably holds one of the braces in place over by the A/C compressor, or some such.

I'll go looking for holes to fill then...:D

Does the intake used on a 2000 fullsize ram van also us this hated plenum plate? or is it only the keg intakes for trucks? Hoping I didn't buy a problem child here...
thanks- rick.

Sorry man. Same intake as on the trucks.

Welcome to DF! :D

Hoping mine tested fine- I saw the TSB that instructed to hook up vacuum gauge to pcv system and look for pressure or vacuum. Hadn't used that gauge in 25 years, so my adapters are long gone- So what I did was held my thumb over the PCV hose for a few seconds to fell vac or pressure- I felt no vacuum and when I removed thumb-I got some blow by wafting gently out of the crankcase- so I guess I'm ok.

Better to do it while motor is out.
 

I an replacing 5.2 with 5.9 so doing this while motor is out. Anything else I should tackle?

Well, the plenum if you haven't already. :)

Aside from that, just clean everything really well, while the motor is out of the way.

Im looking to replace my plenum on my 99 360 in the near future. While i am doing this i want to put on a performance intake manifold. Which one is the best to do? I want one that uses the same throttle body, bolt pattern etc.

You really only get two choices. Hughes Air Gap, or Mopar M1. The mopar manifold is becoming hard to find.... Hughes still seems to be supplying the air gap. Neither option is cheap.

Welcome to DF!

Which one produces more power and what sort of power gains should i expect