No need to be afraid of anything, the H4 LEDs are simple plug and play items, the fan is integral.
Link to the 10,000 lumens 4 cob that I am using
https://www.ebay.co.uk/itm/2x-200W-H...WzTkRdJ_XeJZSQ
Select H4 to fit your headlamp, That's not the same source as mine came from but a lot of the suppliers seem to be out of stock... Word is getting around!
You will notice a big difference if you fit one of these in your Bosch reflector, but the pattern is not great on those, so you will need an adapter and an Autopal reflector to really see the benefit of the more powerful bulb.
Fitting involves taking you old bulb out and replacing with the new one. instead of plugging into the bulb, you simply plug into the lead on the end of the cable. The box in the cable controls the current to the bulb and sorts out the switching of dip/main leaving the dip on all the time. You will notice an instant response from the switch rather than the slow wow with the hot bulbs.
If you want more there is the 96,000 lumens one (sorry not 48,000 lumens as I said above).
https://www.ebay.co.uk/itm/LED-Headl...72.m2749.l2649