See this:
https://www.pentaxforums.com/forums/pentax-lens-articles/152336-cheap-macro-b...lose-work.html
Easiest way to get high-magnification macro optics: Reverse-stacking. Use a long camera-mounted prime (the PRIMARY) and a shorter reverse-stacked manual-aperture lens (the SECONDARY). The magnification is their ratio. Reverse-stack a 25mm MF lens onto some 200mm prime for 200:25 = 8:1 magnification. Downside: Working distance is PK register, about 4.5cm, too damn close.
You could put your 35mm macro lens on several sets of A-type macro tubes or de-glassed A-type TCs. But you'd still be working too damn close.
Easiest+cheapest way to get high magnification and a decent working distance: Medium-format enlarger lens (EL) on extension. Get a 140-160-180-200mm EL (such as from Ilex, Rodenstock, Eastman, Schneider, etc) and a bellows and LOTS of cheap macro tubes. Downside: extension eats light.
If edge sharpness isn't critical: Use a Raynox DCR-250 close-up optic on a *long* A-type or AF lens, like in the 300-500mm range. The Raynox is +8 dioptres with a working distance of ~13cm. Magnification is
F*D/1000 where F is host-lens focal length and D is add-on dioptres. So at 300mm it's 300*8/1000= 2.4x and at 500mm it's 500*8/1000= 4x. Upsides: no light loss, and you retain full lens automation.