Tony, Your block may be a '69-up, but the heads must be from something older...all '69's had bolt holes in the ends, this started in some part of the '68 model year.
Using the short pump is possible, however your fan will be way short to the shroud & the alternator mounts way out beside the head (LONG belt), many mount to the ram horn style exhaust manifold. Also, you would have to use an old style power steering pump/brackets. An aftermarket complete set-up may be an option.
A better plan in my eye if your not wanting to swap the heads would be to use a long water pump, an aftermarket alternator set-up (mid/low mount) & a mid '70's-up van power steering set-up. Hope this helps, Lorne
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