diff --git a/generic-accessors.cabal b/generic-accessors.cabal
--- a/generic-accessors.cabal
+++ b/generic-accessors.cabal
@@ -1,5 +1,5 @@
 name:                generic-accessors
-version:             0.1.0.0
+version:             0.1.0.1
 synopsis:            stringly-named getters for generic data
 license:             BSD3
 license-file:        LICENSE
diff --git a/src/Accessors.hs b/src/Accessors.hs
--- a/src/Accessors.hs
+++ b/src/Accessors.hs
@@ -24,7 +24,7 @@
 import Foreign.C.Types
 
 import SpatialMath ( Euler )
-import SpatialMathT ( V3T, Rot )
+import SpatialMathT ( V3T(..), Rot(..) )
 
 showAccTree :: String -> AccessorTree a -> [String]
 showAccTree spaces (ATGetter _) = [spaces ++ "ATGetter {}"]
@@ -240,8 +240,10 @@
   toAccessorTree _ f = ATGetter $ realToFrac . f
 
 -- other types
-instance Lookup a => Lookup (Rot f1 f2 a)
-instance Lookup a => Lookup (V3T f a)
+instance Lookup a => Lookup (Rot f1 f2 a) where
+  toAccessorTree x f = toAccessorTree (unR x) (unR . f)
+instance Lookup a => Lookup (V3T f a) where
+  toAccessorTree x f = toAccessorTree (unV x) (unV . f)
 instance Lookup a => Lookup (Euler a)
 
 showAccTrees :: (Double -> String) -> a -> [(String, AccessorTree a)] -> String -> [String]