Almost a Gansey, Part One

After many consultations with DS, and waiting until Fall to account for Summer Growth, I have started DS's Gansey. The yarn is Caron One Pound. Yes, Acrylic. Yarn Snob I am not, and the price and easy care make this a good choice for the garment.
While swatching I had 4 spi, but now I get 3.5 spi. So out went the plans to use Ann Budd's book as a springboard, and I'm completely winging it, with the aid of several books. 
Disclaimer: his won't be a true gansey, as it won't have gussets and won't be made out of wool.
References:
Barbara Walker's Knitting from the Top Down 
Sabine Dominik's Cables, Diamonds Herringbone 
Donna Druchunas' Ethnic Knitting: Discovery
A Barebones Description
A modified drop shoulder crewneck pullover, worked from the top down. Garter stitch at the shoulders, 2/2 box stitch with reverse stockinette bands yoke, continuing just past the underarm. Stockinette stitch body. Sleeve welts and body hem to be determined.
BACK: 
Cast on 56 stitches for the back. Knit 4 rows. Start box stitch pattern:
Row 1: (k2,p2) to end
Row 2: (p2,k2) to end
Row 3: (p2,k2) to end
Row 4: (k2,p2) to end
Repeat these 4 rows 5 times. Six pattern repeats.
Row 29:  Knit
Row 30: Knit
Row 31: Purl
Row 32: Purl
Work four  pattern repeats of box stitch pattern ( 24 more rows ). This is to the depth of the armhole. Slip stitches to a spare needle and work the front. 
When the underarm is cast on, work two pattern repeats of box stitch pattern ( Now in the round ) and then work the last ridge as follows: 

Row 57: Knit

Row 58: Purl

Row 60: Purl

Row 61: Knit 

...
( note: This post is being edited to reflect any changes I do on the design.. )

What this looks like to Row 34