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Doe's any one out there in WW land happen to have a mounting bracket template for a 2006 Mercury 90 hp 4 stroke outboard they want to sell or lend. I understand that one size fits most outboards Thanks in advance

make your own with the following!
Obviously, there are four holes, two at top, two at bottom.
Most brands use 1/2" diameter fine thread SS bolts with brass locknuts, but I have seen some Yamaha's mounted with smaller diameter bolts, so check on the diameter your engine requires. Dimensions given are bolt CENTERS. You should always draw the transom top and vertical centerline on your template.

From the top of the transom, both top holes are 1-7/8" down, and the bottom holes are and ADDITIONAL 8" down.

Top holes are a total of 12-7/8" apart, or 6-7/16" from transom centerline.

Bottom holes are a total of 9-7/8" apart, or 4-15/16" from transom centerline.

This is the universal bolt hole pattern, and applies to all brands of engines (assuming they adopted it), at least 1984 and later, from about 30HP on up to 250HP. None of this applies to OMC's blind hole option, which other brands did not use.

Also, bolts through the top holes should have the nuts on the outside, and through the bottom holes, on the inside.

This what I found "out there on the net" for what it is worth.....
The actual BIA standard used by every manufacturer of large outboards today is based on the pattern used by OMC for their then new V-4 outboard introduced in the early 1960s. I believe Mercury adopted this pattern in the late 1970s. I suspect this is what you have but you are not measuring quite precisely enough as you measurements are close but not quite spot on.

The bolt hole pattern is as follows:

The top pair of holes are spaced 12-7/8" on center.
The bottom pair of holes are spaced 9-7/8" on center.
The spacing between the top and bottom pair of holes is 8" on center.
The centerline of the top holes is 2-inches below the top of the engine bracket therefor the holes in the transom should be no greater than 1-7/8" and no less than 1-3/4" below the top of the transom.