Block Insertion Lisp/ Palette command - - HELP!

I'm trying to create what should be a very simple lisp routine, or maybe something that can just be put into the pallet as a macro command. Either way; I'm happy as long as it works.

I need to insert a block named grdot into the drawings, but there are variables. I need it to match the annotation scale, plus a user input prompt for either sheet size B, or D.
If it's D size, then the block needs to be inserted at twice the annotation scale, for B size, it would just need to be scaled at the annotation scale.

I'm not having any luck figuring it out and and I'm relatively new at lisp.

Please upload a sample.dwg

You could write it all in one line or what would be better would be to use a lisp that you pass the block name.
not tested

Code:

---

macro
^c^c^p(if (not insblk)(load "insblk"))(insblk "grdot"))

lisp file
(defun insblk (bname  / sheet sz )
(setq sheet (strcase (getstring "Enter sheet size B or D")))
(cond
((= sheet "B")(setq sz 2.0))
((= sheet "D")(setq sz 1.0))
)
(command "-insert" (getpoint) bname sz 0.0)
)

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