p60 dropin rebuild?

I have a q5 on a round base from a currently dead flashlight.

A UF 501b with a luxeon is $10 at DX. The current 800 mah driver aught to be enough.

Is it easy to open the dropin and put a new emitter in?

800 mah into a Q5 should be plenty bright for most folks. I run one at 700 mah in a 501B host and its in the ~75-100 Lumen ballpark. It gets just barely warm to the touch, and the output is regulated/flat. Its a great task-light for general around the house stuff.

How hard that Luxeon comes out depends on the DX build quality. I have had some just pop right off using a swiss army knife, others were impossible to get apart. One light I tore down completely to the brass pill and LED. I had to COOK it on my stove and BURN the thermal epoxy off. It reeked to he11 and back, but I got the thing apart and salvaged the brass pill.

So in summary... YMMV depending on who at DX applies the epoxy.

Alternately you could get a DC-DC board + P60 module reflector kit for $5-6.
SKU:25518
SKU:5955

OK I'll keep that in mind.

One comes with an approx. 100 lumen green luxeon which I think might be interesting to try for biking. (Higher visibility)

For an extra $1 I think I may try it.

Just buy a single mode R2 drop in , swap the driver out for the one from KD / 1845 , and you may end up with a pocket rocket ..

As long as they actually send you a R2 .. DX and KD do have there moments .