drilling a 7mgt dipstick hole

[miggles]

although this has nothing to do with supras my friend and i are undertaking a 7m conversion into a (1985) 5m cressida.We have swapped the oilpump pickup and the sumps of the 5m onto the 7m due to the fact that the 5m is a front sump and 7m rear so it can fit infront of the crossmember.I am wondering regarding the dipstick hole in the block.There is a flat blanked off section on the front of the 7m block that is where the dipstick hole is on the 5m.What would be the best/correct/cleanest(in terms of not gettin any iron in the internals of the crank while drilling) method of drilling the blank out?Also how do u calibrate the dipstick from the full to add marks.I am also suprised at how similar the 5m and 7m blocks are.most the holes are there in the block but just not drilled and tapped.

 

[moorman]

Best way to do this is with the oil pan removed and engine right-side up. Wrap a rag around the closest section of the crank to catch any filings that spin away from the tip of the bit when it breaches the other side. Use the 5m dipstick tube and your oil level readings will be correct.

 

[PIONEER]

I bent the tube in its original spot, Modified the supra GTE Pump's pickup to work with front sump. Why drill holes in the block if you don't have to

 

[miggles]

cheers for the info guys,theres not much room to bend the dipstick guide over enuff but it looks like there is.We have been discussing using magnets,coolant for the drill,making a shield to stop any swarf gettin tossed around etc.
pioneer- nice to see the assembly lube wasnt in short supply