As a former HD mech many moons ago, I have a little know how. Not saying I know it all mind you....

Got my bike used with 320000 km in 2019, it already had v and h monster ovals, boom speakers on the standard bars (hmmm not sure about them),led lights and a top box which I removed immediately.

Since then I have fitted a hi flow element and cut a heap out of the airbox, but to the naked eye it looks stock.

Made my own breather which uses the stock 90 degree bends and some oil line which runs into some braided line that I have routed down to the underside of the gearbox using a small crankcase breather. Used some tee and 90 degree fittings from bunnings from memory. This stops all the gunk going back into the chambers and helps to keep it a little bit cooler and keeps the piston tops free of carbon.

Drilled out the plugs in the mufflers using a big holesaw on a cordless drill, opened them up nicely.

Fuelpak 3 for the fuel mapping, not sure a dyno is worth the exorbitant asking price so it has never been on one. Guessing bteween 80 and 85 hp and around 100 odd foot pounds of torque.

Drilled out the cat with a 13mm drill on an extension( as much as I could get anyways). Yeah I know but it is better than nothing I believe and I also wrapped the cat and some of the rear header in heat wrap to stop the heat rising up, this actually works well and all you need are some large hose clamps.

Again to the naked eye it looks stock and the wrap is unobtrusive. 

I have fitted a 120mm computer fan behind the rear head to suck the heat out on when it gets too hot. Its not as good as love jugs or jims fans but it helps and easy to fit with some  90 degree brackets and hooked up to the accessories wire, running through the spare switch on the right hand side of the  nacelle. Not to mention it didnt cost 500 bucks...

Rear shocks courtesy of Ikon, these are superb and I would highly recommend them. The service is great from these guys and not only are they half the price of progressives etc, they take all the wobble out and do what they are supposed to do.

Other stuff includes chrome derby, rear master cylinder cover ,axle covers, heated grips, black console insert, redone seat by Johnno at Bitchin stitch,headlight cover extension, indicator cover extensions,chrome taillight cover,  lightly tinted shorter screen courtesy of Eagle screens in WA.($250).

Was going to get Woods 222 cams but after a good hard think $2500 isnt worth an 5 to 7 hp just twist it a bit more !!

So you dont really need to spend a sh@tload of money to make it go that little bit better...