Radiator Valve Extensions

Radiator Vent Extentions

We are swapping out several air vents on baseboard radiators and plan to replace with maid-o-mist or varivalve. For reasons of aesthetics and in some cases accessibility, it would be useful to use either a horizontal extention from the radiator or alternatively an "L" extension from the radiator (permitting use of a straight value, into the "L", rather than using an angle valve, into the radiator) (in either case the horizontol or "L" would extend through an end cover to the radiator).

Is it wise to use an extension in this manner or would functionality be degraded in any way? Are these extensions commercially available (I have not been able to find) or would they have to be custom made?

Thanks for any info.