Don’t have any Lockwood V7 blanks, so taking a tip from LocksmithArmy, I tried modifying a KW1 blank. I started by picking, then field stripping the lock, so that I could more easily see the modifications needed using just the key and the plug. Used a cheap-donkeyed set of diamond needle files from Harbor Freight to make the modifications, which allow better control than a dremel tool. Did not list measurements for how much to file the warding because that will depend on the specific keyway. This key fits two of the three V7s in my collection, but the third lock will only require minimal filing to fit. That will occur on another blank, since this one is already working.

Below are the measurements I took with my cheap micrometer comparing only the differences between the KW1 and the modified KW1 blanks. I have included both forms of measurement for people in more places. If the specification is not listed, I did not change it.
Normal KW1 Modified KW1
Blade length from shoulder to tip:
1.095” (27.81mm) 1.108” (28.15mm)
Blade Height:
.335” (8.51mm) .306” (7.77mm) trimmed on top AND bottom!!!
Bottom ward:
.024” (.60mm) .015” (.40mm)
Shoulder to first bitting on V7: .236” (5.98mm)
Distance between bittings: .125” (3.17mm)
NOTES:
The length of the blade from shoulder should be longer, but as the seventh pin was a deep cut, I let it ride on the ramp at the tip of the key. Yes, that is a no-no for locks in actual use, but it works beautifully for my toy that will never see the wear of a lock in use.
I increased the length of the blade by filing back the shoulders of the key.
Filed bevels on the parts highlighted below:

Have fun with this!
Gordon