I need to get a press so before I splash out 50 euros on a purpose made one I thought I’d try the homemade route. I had one bookmarked but it’s gone so does anyone know where there’s a guide?

I made one up from some (IIRC) M12 or M14 threaded rod, square washers and bolts – it’s essentially the same as a homebrew headset press.

It’s useful if you can get the Park BB30/PF30 bushings (part no 668) from somewhere though – help keep the bearings centred on the rod – I got mine with Park BB30 bearing removal tool (and the BB86 ones, for some random reason)

Oh yeah, and make sure you grease it all up before you use it.

I use a 30mm and 32mm socket on the ends of some threaded bar.
another option is to bang the new bearings in using the old bearings and a lump of wood.