M20x1.5 SS Hollow Tube - Oil Filter Adapter / Thermal Block Bypass

I got my machinist to knock me up a bypass for my thermal block (oil warmer/cooler).
I worked out the thread was an m20x1.5, just like the oil filters.
BUT for some reason I think the tapped threads in the oil pump were slightly off OR I broke some threads previously and when removing the original bolt it pulled the threads and ruined the rest.

So the hunt for a m20x1.5 tap begun, I didn't need some special HSS bit that costs $80.
I managed to find a cheap set that has all the way to M24 in it.











































Quality of the set seems surprisingly good, its from BORUM importers -
Metric:
m6x1.0, m6x0.75, m8x1.25, m8x1.0, m10x1.5, m10x1.25, m12x1.75, m12x1.5, m14x2.0, m14x1.5, m16x2.0, m16x1.5, m18x2.5, m18x1.5, m20x2.5, m20x1.5, m22x2.5, m22x1.5, m24x3.0, m24x1.5
14 1-1/2” OD Dies
m6x1.0, m6x0.75, m8x1.25, m8x1.0, m10x1.5, m10x1.25, m12x1.75, m12x1.5, m14x2.0, m14x1.5, m16x2.0, m16x1.5, m18x2.5, m18x1.5
6 2” OD DIES
m20x2.5, m20x1.5, m22x2.5, m22x1.5, m24x3.0, m24x1.5
5 Screw Extractors
No#1, 2, 3, 4, 5
1 “T” TYPE TAP WRENCH
1 TAP WRENCH
2 2” DIAMETER DIE STOCK WITH 1-1/2” ADAPTOR
1 PUNCH