Dyno tune needed for manual swap?

[kipps]

I realize that manual swaps are pretty uncommon, but thought I'd ask anyway.

Engine is a 2010 5.3 LMG engine. I'm told 5.3's never had manuals.

I'm not making any changes to the engine, except for the manual tranny. Are manual flashes good enough that I can get by with a mail-order tune, or will I likely need a dyno tune?

Dyno or not makes some difference where I send it now.

Related question: I'm starting out with my stock sm465, with a possible future upgrade to a nv4500. Would either a mail-order or dyno tune be affected by a future change in gear ratios? The engineer in me is thinking it would be possible to tune an engine to predict what gear it's in based on the VSS, and be custom tailored for each gear. Is this the case, or am I overthinking it?