There's plenty of people who have done custom movements of these items, and that bracket is one of the first things to get out of the way. Build yourself a nice bracket, get some decent silicone vacuum tubing that securely fits each fitting, and dig in. If you peel back the coverings on the wires, they'll give you some flexibility to route elsewhere, and re-tape and cover when you're done.
You can do something simple, like this bracket I make for my buddy's car back in 2007:
You can also swap to the Series 3 (L32) 2-bar MAP sensor, which has the smaller size like the L36's. It'll tuck into spots even easier, but you'll need to adapt the wiring harness connector. I did this on many top-swapped L36's, and on my 2004 Turbo Regal to run the L26 upper intake cleanly.
Currently building a vacuum manifold to sit on the back of my Holden intake plenum, and I'll post pics when that's finished (gotta block a bunch of extra ports on the Holden, first). It's a simple one that I can route to all the turbo items, along with the normal ones:
All sorts of options, just use your imagination. The Gen V M90 swap gives you even more options, with the TB adapter plate and EVAP port providing new sources. Here's mine that I ran for a couple years, before putting it in storage to run an MP112 for a few years:
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