UK choropleth map challenge - postcodes in 3-4 digit format

Ignore that. It isn't even that hard. With the caveat that I still might have misread the thread.

It looks like the Postcode shapefile zip contains 3 shapefiles with the Distributions directory: Areas, Districts and Sectors. Looks like Districts is what you want.

So something like this might get you to the point where you can start plotting using ggplot and geom_sf:

library(tidyverse)
library(sf)

#Download UK postcode polygon Shapefile
 download.file(
 "http://www.opendoorlogistics.com/wp-content/uploads/Data/UK-postcode-boundaries-Jan-2015.zip",
"postal_shapefile"
 )
unzip("postal_shapefile")

uk <- read_sf('Distribution/Districts.shp')

region.scores <- data.frame(stringsAsFactors = FALSE,
              NAME_3 = c("BB7","BB1","PR5","CA3",
                       "DG12","CA15","CW1","ST7","CW9","PR4","PR2","PR7",
                       "ST17","ST18","ST16","ST3","ST4","TF9"),
             Score = c(0.717647058823529,
                       0.761194029850746,0.4375,0.777777777777778,0.764705882352941,
                       0.727272727272727,0.807017543859649,0.830769230769231,
                       0.868421052631579,0.819672131147541,0.732673267326733,
                       0.741379310344828,0.811764705882353,0.761194029850746,
                       0.844827586206897,0.68,0.855263157894737,0.857142857142857),
              Shop = c("AAA","AAA","AAA","BBB",
                       "BBB","BBB","CCC","CCC","CCC","DDD","DDD","DDD",
                       "EEE","EEE","EEE","FFF","FFF","FFF"),
              Cor1 = c(53.874,53.756,53.731,54.907,
                       54.99,54.712,53.103,53.088,53.259,53.754,53.778,
                       53.645,52.789,52.814,52.813,52.981,52.995,52.897),
              Cor2 = c(-2.386,-2.462,-2.656,-2.939,
                       -3.251,-3.481,-2.434,-2.265,-2.501,-2.833,-2.708,
                       -2.652,-2.099,-2.081,-2.118,-2.122,-2.183,-2.469))

uk <- left_join(uk, region.scores, by = c('name'='NAME_3'))

Ron.